Process for treating, impregnating, seasoning, and stabilizing wood



same time, namely, the driving out of the Patented Oct.- 22, 1929 UNITEDSTATES PATENT OFFICE GEORGE ELTON RICE, or BROOKLYN, New YORK, Assmrron,BY manor AND MESN'E ASSIGNMENTS, TO CONSERVATION CORPORATION OF AMERICA,A CORPORATION-OF DELAWARE v PROCESS FOR TREATING, IMPREGNATING,SEASONING, AND STABILIZING W001i) No Drawing.

The present invention relates to processes for treating, impregnating,seasoning and stabilizing wood, and is particularly an improvement overthe processes disclosed in my copending applications Serial Nos. 726,83and 7 35,218, filed July 18 and Aug. 30, 1924, respectively. i

One of the ObjGCtS'Of the invention is to treat the wood with a solutionthat removes the extraneous matters from the wood, such as fats,starches, sugars, gums, acids, oils, dyes, resins, tannins,albumen,etc., and which will simultaneously dehydrate the wood so ,as to reducethe moisture content of the treated Wood to the minimum, withoutrequiring artificial or kiln drying. Another object is the treatment ofthe wood to remove the extraneous matter, including moisture, and tosimultaneously saturate or impregnate the wood with waterproofing anddehydrating material, so that the treated wood will be waterproof, dryand ready for use in a short time after treatment.

A further object is the treatment of the woOd with such materials as toeliminate the extraneous matters from the Wood and to si-' multaneouslyimpregnate the wood with a material or substance that will preserve andwaterproof the Wood as well as enabling/the wood to take paints,varnishes and other finishing materials readily and advantageusly.

The invention also has for an object to combine in a single operationthe removal of the extraneous matters from the wood, and

, wood, contrary to the solutions as disclose in the aforesaid copendingapplications, /is

, non-aqueous, in that it contains no water,

thereby not only assisting materially in driving the water or moisturefrom the wood, but also eliminating both the saturation of the wood byWater in the solution and the requirement for subsequent artificialdrying. In this way, two advantages are obtained at the Applicationfiled Apri18, 1925. Serial No. 21,695.

natural moisture from the wood, and the elimination of the entryof'moisturelfro'm the solution into thewood during treatment;

The dehydration of the wood can therefore 1 impregnate the wood toeliminate the extraneous matter therefrom and to dehydrate the wood, andat the same time to protect and preserve the wood for subsequent use.

The proportions of the constituents of the solution may vary fordifferent woods, and as an example for freshly felled or partly airdried maple, birch or sweet gum, ash, mahogany, and similar woods, thesolutidn will com prise the following:

Pounds Linseed oil a 1000- Sugar 150 Sodium fluoride 35 Sodium sulphate15 The proportion of the sugar is substantial-v l 15%, by weight, of theamount of oil, and the proportions of sodium fluoride, and sodiumsulphate are substantially 3 and 1% percents, respectively, of theamount of the oil. The linseed oil used is heat treated to fix the footsor gummy content. The saccharine matter or sugar component of thesolution may be ei ual parts of maltose and cane syrup or moasses. Maltsugar and cane sugar (granul ted or brown) may be used in place of matose and the syrup. A sweet potato syrup may also be used in lieu ofcane products when available.

Although linseed oil is mentioned, other drying ve etable oils may beused, such as tung, peri lla, 'soya bean, and similar vegetable oils, orcombinations thereof.

The in redients are mixed at a temperature varying rom 100 to 120degrees F., the 011 bein heated to such temperature and thesaccharine-and other materials then being added to and mixed with theoil.

The wood may be treated in any shape'or form, either timber, lumber orwood prod-.

nets, and timber may be treated with or without the bark being removed.The term wood. also includes vegetable fibres for which the process issuitable. The wood is immersed in the solution, an this can be .done inseveral different ways, such as by loading the wood in piles or stacksin or on a rack or flat truck, skid or other conveyance, which is runinto a tank, or the wood may be conveyed into the tank by an overhead orautomatic conveyor, or may be piled of stacked in the tank. If the woodis lowered into and elevated from the-tank, then the sides and ends ofthe tank may be solid, but' if the wood is conveyed on tracks into andout of the tank, the ends of the tank are arranged to open for theentrance and exit of the conveyors or vehicles carrying the wood. Anopen rectangular tank is preferably used, although it is preferable torovide a hoodor-cover for the tank to con ne thevapors so that theycanbe drawn off and con- ;served for the recovery of valuable byproducts.

After .thewood is placed in the tank and held therein so as not to floatto the top of the solution,the solution is delivered into the tank tofill the tankto a level several inches above the wood. The solution isheated,-.such as by submerged steam radiators at the bottom of the tank,until the solution reaches a tempera- 1 ture of 130 degrees F. andismaintained at such temperature for about one hour, and then graduallyraised to between 210 and 212 degrees F. and maintained at suchtemperature until no furthepexcess matters are seen leaving the wood.Then, after a period varying from one hour to several hours, based onthe thickness and. density of the wood, the heat is shut off, and thewood and solution allowed to cool until no further bubbles are observedleaving the wood. The wood is then removed from the solution or allowedto remain in the solution while it cools until the wood has becomecompletely impregnated with the solution, and the impregnation may beregulated by the length of time the wood is permitted to remain .in thecooled solution. The impregnation may thus be varied according torequirements.

During the impregnation period, when especially dry wood is required,the wood is according to the amount of impregnation of the waterproofingmaterial desired, based on re uirements.

s soon as the wood is removed from the solution,.the tank and solutionare ready for the next'load of wood.

heatingand cooling periods may be repeated as indicated. The lengths ofthe heating and cooling periods are determined by the nature of thewood'being. treated and results desired.

During the'treatment or boiling of the immersed lumber, the. solutionpenetrates the wood, and'owing to osmotic action the solution acts underpressure from all sides in the Wood, and a steady stream of extraneousmatters are expelled from the wood until the wood is cleansed. The woodis also sterilized, the poison being combined with the fibres andinterstices, and the crystals of the poison remain in combination withthe fibres and interstices and have reserve power so that theyconstantly expel toxic poison for indefinite periods. The poisonprevents further action of fungus or wood destroyers and avoids theliability of dry rot occurring.

The fats, starches, sugars, gums, acids, oils, dyes, resins, tannins,albumen and other extraneous matters are removed from the wood inasimple, practical, and eflicient manner, a nd are replaced by thesolution or material that preserves and compacts the fibres; reducingthe cell spaces, and filling the wood with the oil which Waterproofs thewood as well'as encapsuling in the fibre and cell walls the toxic poisonthat inhibits the wood against the attacks of wood destroyers, dry rotand other fungus.

Freshly felled or green timber as well be seasoned rapidly by thepresent process, as well as being insect-proofed and waterproofed at thesame time, in a single operation, without resorting to artificialdriers. The linseed or other vegetable drying oil will waterproof anddehydrate the wood,

as well as serving to encapsule the toxic.

poison and retain same in the wood indefinitely. By timing the length oftreatment or immersion of the wood it is possible to reduce the moisturecontent of the wood to a desired percentage, without requiringsubsequent kiln or artificial drying, it being notedthat the solutioncontains no water so that as'the moisture is forced from the pregnatedwith the oil will have 'a perfect aflinity for practically all finishingmaterials. Furthermore, there is a saving inthe amount of finishingmaterial necessary, inasmuch as the absorption-of the finishingmaterials by the wood is reduced, although the finishing materialadheres effectively to the superficial portion of the wood.

l/Vhen treating the wood the substances extracted from the wood arerecovered in order to obtain valuable by-products. These 4 are obtainedfrom the scum rising tothe surface of the solution which is skimmed 0d,and also from vapors passing from the solution which are drawn off andcon densed. The treatment eliminates the. ex-' traneous matterfrom thewood without fracturing the cellwalls orfibres, thereby reducing seasonchecking and degrading. During the treatment, the cell walls areswollen, releasing the air combined with the fibres and cell walls,without breaking down the cell walls, and the spongy or soft portions aswell as the summer or immature growth of the wood are filled, and theabsorption properties of the wood equalized.

The saccharine solution containing maltose and cane syrup or molassesproducts has been found to be especially efi'ective, the maltose, whichis fundamental monosaccharose, being strongly dextro-rotaryand havinggreater osmotic action than dextrose or dextrin'. The maltose forms aphenyl ozazone combined with the syrup or molasses (cane or beet) orneutral su ar, which is of advantage in carrying out t e process and inthe results obtained.

By combining the oil with the sugar or saccharine matter, this willenable the entire process to be carried out with a single treatment ofthe wood, eliminating water or moisture from the-sol ution, so that thewood is simultaneously .cured, cleansed, .oisoned, dehydrated andwaterproofed. e toxic poison combined with the solution will alsoprevent fermentation of the solution when not being used, and the poisonbeing encapsuled by the oil inthe treated wood will be prevented frombeing liberated'too free-' 1y,- the'reby,keeping the poison encapsuledor'imprisoned to indefinitely repel destructive organisms and fungi andinhibit the wood against future attacks from wood destroying insects,fungi and the like, as well as preventing moisture from entering the,wood, which if it occurs, may cause the wood to shrink or swell, or torot. .The vegetable oil, or a combinatibn of vegetable oils, such ashereinbefore mentioned, will also assist in removing the excess mattersfrom the wood, as well as stabilizing the wood. The oil renders the wooda non-conductor of electrical energy so that the wood may be used forelectrical insulating purposes. The oil also assists in preventing thewarping or shrinking of the wood.

The process is based on the underlying natural laws that all colloidalsubstances, of which wood is the most important, absorb their similars,and that all colloidal substances become stable after being'raised to adegree of heat substantially peculiar to each of them, from which itresults, that in carrying out this process, the solution which isabsorbed by the wood will be thoroughly assimilated by the tissues andheld in comb nation with the fibres of the wood and in the interstices,

- and no matter how hard the wood is it will be cleansed of extraneousmatters, and the live, summer or sap wood stabilized to equal the heartor fixed growth of the wood, without the aid of vacuumor pressureequipment in the treatment required. The process is a natural one, underatmospheric pressure, being the action of a similar on a similar, and asthe wood is impregnated by capillary and osmotic action,.the excessmatters removed are replaced by the material with which the wood isimpregnated which will dry and oxidize slowly in combination with thefibres, interstices and cell walls, and the cells may be completelyfilled when required.

Having thus described the invention, what is claimed as new is anon-aqueous saccharine wood consisting in impregnating wood with anon-aqueous saccharine solution heated to or above the boiling point ofwater. I v

3. The process of cleansing, -dehydrating and impregnating woodconsisting in immersing wood 1n a non-aqueous saccharine solu tion.

4. The process of cleansing, dehydrating and impregnating woodconsisting in immersing wood m a non-aqueous saccharine solu-' tionheated to or above the boiling point of water.

5.-The process of cleansing, dehydrating and impregnatingwood consistingin simultaneously impregnating wood with oil and sugar. I 6.-The processof cleansing, dehydrating and impregnating wood consisting in simultaneously impregnating woodwith oil and sugar heated to or above theboiling point of water.

' 7. The process of cleansing, dehydrating and impregnating woodconsisting in immersing wood in a mixture of oil and sugar. 8. Theprocess of cleansing, dehydrating and impregnating wood consisting in1mmersing wood in a mixture/of oil and sugar heated to or. above theboil-ing point of water.-

9. The process of cleansing, dehydrating and impregnating woodconsistingin simultaneously impregnating wood with sugar and vegetable oil. V

\ 10. The process of cleansing,- dehydrating and-impregnating woodconsisting 1n simultancouslyimpregnating wood with so ar and vegetableoilwhea'ted to or above the oiling point of water.

11. The process of cleansing, dehydrating and impregnating woodconsisting in immersing Wood in a mixture of sugar and Vegetable oil.

12. The process of cleansing, dehydrating.

and impregnating woodco l'sistin'g in immersing wood in a mixture'ofsugar'and vegetable oil heated to or above'theboiling point of water.

13. The process of cleansing, dehydrating and impregnating woodconsisting in immersing wood in an oil-saccharine mixture, heat ing themixture to or above the boiling point of water, andthen cooling themixture before removing the wood.

14. The process of cleansing, dehydrating.

and impregnating wood consisting in immersing wood in a. mixture ofvegetable oil and sugar, raising the temperature of the mixturesignature.-

to or above the boilingpoint of water, and then permitting the mixtureto cool before removing the wood. Y

In testimony whereof I hereunto aflix my GEORGE ELTON RICE.

